Method and apparatus for making fiber-reinforced sheet material



March 29, 1960 f c. sHoRTs R'e. 24.804

METHOD AND APPARATUS RoR MAKING FIBER-REINFORCED SHEET MATERIAL Original Filed Oct. 2, 1952 5r Sheets-Sheet 1 Original Filed Oct. 2, 1952 BY @g4-241 M 2 www A A f roem/TV5 March 29, 1960 c. sHoRTs Re. 24,804 METHOD AND APPARATUS FOR MAKING FIBER-REINFORCED SHEET MATERIAL Original Filed Oct. 2, 1952 5 Sheets-Sheet 3 IN VEN TOR.

@ALL/00N af/0R75) BY @Mlm A Trae/VE V5' March 29, 1960 c. sHoR-rs Re'. 24,804

METHOD AND APPARATUS FoR MAxxNG FIBER-REINFORCED SHEET MATERIAL Original Filed Oct. 2, 1952 5 Sheets-Sheet 4 March 29, 1960 c. sHoRTs Re. 24,804

METHOD AND APPARATUS FOR MAKING FIBERREINFORCED SHEET MATERIAL Original Filed Oct. 2. 1952 5 Sheets-Sheet 5 `METHOD AND "APPARATUS Fok MAKING FIBER-.REINFORCED SHEET MATERIAL Calhoun Shorts, Bellevue, Wash., assignor to Filou Plastics Corporation, El Segundo, Calif.

original No. 2,784,763, dated March 12, 1957, serial N 312,819, October 2, 1952. Application for reissue February 21, 1958,`Serial No. 716,830

40 Claims. (Cl. 154-1.75)

I Matter enclosed in heavy brackets appears in the original patent but forms no part of this reissue specification; 'matter printed in italics indicates the additions made by reissue.

`The apparatus of this invention is utilized for performing a continuous process of production of sheet material, and in particular of translucent, tibet-reinforced resin sheet.

While the apparatus hereinafter described may be used in the manufacture of sheet material of various types, itis intended particularly for use in making a resin sheet reinforced with Vglass or comparable bers embedded in the set resin.

An object of the present apparatus is to produce such fiber-reinforced resin sheet by a continuous process uniformly and accurately, although rapidly. Such product will besmooth, hard, strong and of uniform thickness, having substantially no occluded air bubbles. Such apparatus is substantially automatic in operation so that it can produce the sheet material rapidly `and economically, can be prepared quickly to begin production and requires minimum attention and interruption after initiation of production.

It is also an object in setting the resin by application of heat to utilize such heat effectively and economically without any portions of the sheet area being overheated or insuiciently cured.

It is a further object of the yapparatus to form the sheet as it is produce into any desired cross-sectional shape: flat, corrugate, V-crimp, channel, arcuate, etc.

A particular object where surface lms of material subject to shrinking by the application of heat are used is to preheat such surface iilrns before the resin has been set appreciably, so that substantially all of the surface lrn shrinking is completed before the sheet is formed to its desired cross-sectional shape, and the setting action of the resin has progressed appreciably.

An additional lobject of the apparatus is to edge trim the sheet as itis produced and to cut it otf into desired lengths without interrupting the continuous production process.

It is also arrobject to move sheet material through the entire apparatus by traction on the formed sheet applied at the discharge end of the apparatus.

Essentially the apparatus draws through it upper and lower surface lilm's, constituting carrier elements. Resin is fed onto the lower surface film, leveled to a predetermined depth and retained upon the film as a pool not extending closer to the edges of the film than approximately two inches. Into the resin is laid the reinforcing ber material. The reinforcing material sinks into the pool of resin and all air in the reinforcing material is displaced by the resin. The upper surface lm is applied, andk ,the composite `sheet isrolled to consolidate the laminated 'structure to a predetermined thickness while the edge portions kof th 'surface ltns from whichresin has been excluded `are `sealed with A:aribbon .of suitable adhsive. The laminated structure is vthen drawn through a sris of forming shoes `while the sheet is heated to Vother desired form.

set the resin. Such shoes may be flat or of corrugated or The set resin is then cooled, and the finished sheet material is'edged and cut into panels of desired length. v

Additional features and advantages'of the sheet forming apparatus will be discussed in the following detailed description of it.

Figure l is a general side elevation View of typical sheet forming apparatus according to the present 'invention.

Figure 2 is a side view of the feed end of the vapparatus with parts broken away to show internal structure, and Figure 3 is a plan view of one side of this portion of the apparatus with parts broken away.

yFigure 4 is a longitudinal vertical section through the central portion of the apparatus, Figure 5 is a transverse section throughV such portion online `5-'-5 of Figure 4,

and Figure 6 is a transverse section through such'portion of the apparatus on line 6-6 of Figure 4.

vFigure 7 is a side view of the discharge end of the apparatus with parts broken away, and Figure 8 is a plan view of such portion of the apparatus having parts broken away. Figure 9 `is an enlarged transverse section through the apparatus taken on line 9-9 of Figure 7.

Figure 10 is a top perspective view of a fragmentary portion of the feed end of the apparatus having parts broken away, Figure l1 'is a fragmentary side elevation view of the same portion ofthe apparatus, and Figure 1Q is a fragmentary sectional view of such portion'of the apparatus taken on line 12-12 of Figure 11.

Figure 13 is a side elevation view of the feed end of a modified type of sheet forming apparatus.

Figure 14 is a side elevation View of the feed end of still a different type of sheet forming apparatus.

Theapparatus is composed of three principal sections. rEhe rst of 'these is the feed section in which supplies of upper and 'lower surface lm material, resin and glass mat are provided, fed into the machine and consolidated into mat form. T he second section is the resinsetting section in which the composite sheet is formed 'into the desired shape, such as corrugated, and the resin is first heated, then cooled and finally reheated to effect setting of the resin. The third section of the machine is the propelling and trimming section which ,incorporates the power mechanism operable to pull the composite sheet through the machine and trim-'mechanism for ediging the sheet and cutting it into sections of desired length. y

Glass mat, which is the preferred type of reinforcing material used in manufacturing the fiber reinforced resin .sheet product, is composed of a number of layers of glass fiber bundles, crossing at random and bonded loosely together with resin. Each bundle of fibers is composed of strands two or three inches in length, untwisted but of sucient number to form a heavy thread. These bundles of istrands are bonded together securely enough-to form a loose mat which can be handled without coming apart. Glass roving which is another type of reinforcing material which may be used in manufacturing fiber-reinforced resin sheet is a loose aggregate of continuous glass fibers wound as a yarn upon a spool. When used with this apparatus sutiicient spools of roving are placed above the apparatus and their ends in close parallel alignment are drawn through the apparatus just as is the glass matin the description to follow.

Glass cloth or other woven fibers may also be used in this apparatus to manufacture reinforced resin sheet. The resin vpreferred for use in themanufacture f 'sle't material produced by the present apparatus lis one of low viscosity which will readily impregnate the reinforc-l ing materialand on exposure to hatwill setint a dense infusible state. For translucency a clear light-stable sesos l3 resin 'his desirable. For decorative purposes a light-colored resinxwhich may be tinted by the addition of pigments or dies, is desirable. For clarity a resin which has an index of refraction closely matching that of the reinforcing material is desirable. All these characteristics may be "found in a family of resins called polyestersf which are well, known to'be settable by the process of polymerization. The material used for the surface elements should be thin, nonporous, inexpensive, and .sufiiciently lstrong to party the resin and reinforcing fiber material entirely through the sheet forming apparatus without being ruptured. It has been found that cellulose film, that is, cellophane, meets these requirements, although it is entirely feasible to use other materials such as cellulose acetate film and polyethylene film, for example, which, like cellophane, will part from the set resin sheet, or polyester lrn which will adhere to the resin and become an integral part of the finished s heet.

."The operation of the apparatus will he described using cellophane as the surface films, glass mat as the reinforcing material, and polyester type resin.

The surface film material is supplied in the form of rolls, and in the feed section l of the machine is mounted vran upper surface film roll and a lower surface film roll shown in Figure l. A guide roll 12, over which the Vlower Vsurface film passes, is located so that the upper side ofv its `periphery is coplanar with the surface of the mat forming table 13. Surface film material UF from the roll 11 passes downward under a tightener roll' 14, braked or .of friction type to tension the material in the direction of its movement, and then up over the roll 12 onto the mat forming table. From the roll 10 the upper surface film material passes around the tightener 15, the rolls of which v may be suitably braked to tension the film, and then under a guide roll 16 mounted for vertical movement, guided by rods 17 in registry with a lower roll 18, to exert pressure on the sheet being formed. y

It will be seen that the lower surface film material LF passes along the forming table for a considerable distance between the roll 12 and the roll 16 before the upper lm material is laid over it. During this travel resin utilized in formation of the sheet is spread on the lower surface film from a row of apertures in the bottom of the resin trough 2 which may be supplied continually or intermittently as required from a reservoir by a supply pipe 20. The iiow of resin from the apertures of this container is regulated in accordance with the speed of travel of the surface film material by appropriate adjustment of a slide valve plate 21 in the trough bottom apertured correspondingly to the apertures in the trough bottom so that the proper amount of resin is furnished to form a sheet of the desired thickness. The resin thus supplied is leveled and reduced to the ex'act thickness desired by the doctor blade 22 extending across the sheet 4forming table. The elevation of the doctor blade may be regulated to provide the correct amount of resin depth. It has been found that air bubbles in the finished sheet are. greatly reduced by laying the reinforcing material into a layer of resin rather than first running the reinforcing material through a dip tank or placing the reinforcing material on the lower surface film and spreading the resin upon it. When fibrous reinforcing material is laid upon a layer of resin and time is allowed for it to sink into the resin, air in and between bundles of fibers is displaced Iupward as impregnation progresses and no air is trappedv This is not true of any other method of impregnation and is one of the novel features of this apparatus and method.

If the quantity of resin supplied on the lower surfacefilm LF is not quite great enough to saturate the rein-- forcing material, some additional resin, as necessary, ma)r be added on top of the reinforcing material after it ha sunk into contact with the lower surface film.

g A rollpf glass mat .23 is supported on the frame ofy section 1, and the glass mat sheet GM passes around and beneath the glass matlaying-.guide roll 24 which is diss.

posed just above the upper surface of the resin layer and guided for vertical adjustment along guide rods 25. Between the roll 24 and the pressure roll 16, therefore, the glass mat will be inclined at a very small angle relative to the sheet forming table 13, so that the glass mat will gradually be lowered into theresin before the surface tilm is applied to the upper side of the resin and glass mat. Additional resin inay be supplied from an auxiliary supply pipe supported just ahead of the rolls 16 and 18. Resin may be dispensed from this conduit through a spout 20', which can be swung to various positions in which an operator may note that the supply of resin on the glass mat is inadequate. An excess of resin at this point will not be objectionable, because the rolls 16 and 18 will squeeze it back and distribute it so that a uniform character of composite sheet will be discharged from the rolls.

The resin used in the fabrication of the sheet material is quite fluid, and when leveled on the lower surface lm by the doctor blade 22, tends to spread laterally toward the edges of such surface film. In order to provide a. resin pool of sufficient depth to fully impregnate the glass mat as it is laid into the resin, it is necessary to provide a barrier alongeach edge of the lower surfacefilm on ythe table 13 ahead of pressure roll 16, and to prevent leakage of resin out of the pool a tight seal must be provided be# ytween the barrier and the periphery of roll 16. While such barrier and sealing mechanism is shown generally in Figure 2, the details of it are shown more clearly in Figures 10, 11 and 12. Since the mechanism is the same at opposite sides of the lower surface film, it will be neces sary to describe only that at one side as shown in these figures. l l

--From a location at least some distance to the feed side of the doctor blade 22 to a location closely adjacent lto the periphery of roll 1'6 extends a narrow channel ytrieniber 3 with its web lying on the table 13 and with its flanges projecting upwardly. This channel extends parallel to the direction of movement of fthe sheet material, and re ceived partially in the channel and riding on the lower surface film LF is a strip 30 preferably of wood. The feed end of this strip is held by a spring clip 31 secured to it and engaged with a bar 32 supported froin Ithe fratrie of the apparatus, such as on the doctor blade 22. The strip 30 is so positioned that it presses the cellophane film somewhat into the channel 3, as shown in Figures 10 and 12, and produces a tight seal between the lower edge of the strip and such film. No support or presser element need be provided for the rest of the strip because its weight and the'pressure on it reacting from roll 16, as described below, will be sufiicient to hold it in firm sealing engagement with the lower film. The end of this strip is dis posed as close as feasible to the periphery of such roll without actually contacting it, and the void between the strip end and such roll is filled by a further sealing element, such as a small paint brush 33, which may be supported conveniently from the adhesive dispensing container 26 by a clamp bracket 27, and will transmit light pressure from the roll onto the strip end.

While the brush 33 cooperating with the end of strip 30 adjacent to roll 16 must substantially fill the angle between the periphery of such roll and the lower surface film LF, the brush bristles must not be subjected to appreciable tractive effort of the lower and upper rolls tending to pull the brush between them.

The periphery of roll 18 is received in a slot extending transversely across table 13, and the periphery of such roll projects upward slightly above the upper surface of such table so as to maintain a pool of resin adjacent to the rolls through which the glass mat passes to insure its complete saturation before moving between the rolls. Conveniently the lower roll has each of its endscradled 'in spaced rollers 19 suitably supported from the apparatus by a plate 19 carrying one end of each of rolls 19 and also serving as a stop to limit lengthwise movement of roll 18.V 4.Alongside the end of roll 18 is mounted a brush .s4-beneath the table" '13,' andY supported. by' s suitable:

bracket 35 ced' 'by such table'. Thsvbru'sh is inclined' f'tnwax'dlyv and upwardly' to press thelowersur'face'filx'n LF against-'the brush 33 and the roll 16 to afford an eieetive s'e'al preventing" leakage of resin outwardly among the surfaces of this roll.

The glass matv sheet -will be of a width to lie between the'st'rips' 30 so' that only the lower surface film is pressed' by such strips into the channel 3. The edge portions of s'uch lower surface film outside of strips 30 resting on table 13 will thus be exposed, and adhesive may be dripped onto such marginal sheet portion from the container 26, the amount of ,adhesive thus applied being regulated by the valve 28. The drops of glue thus supplied may be spread to form a ribbon on the sheet, such as by a brush 29l also supported from the bracket 27 as shown in Figure ll, justY before the upper surface film UF is applied by the roll 16. Such adhesive should be of the type which will set" quickly, so that the upper and lower films are secured together shortly after the composite sheet passes the rolls '16 and 18.

The composite sheet materials discharged from rolls 16 and 18 will be composed of a central layer of glass mat thoroughly impregnated with unset resin having its upper and lower sides covered with transparent film material such as cellophane, the edges of which surface films LF and UF extend at least several inches beyond each edge of the glass mat filler, and such projecting marginal portions of the surface films are secured together by a ribbon of suitable adhesive to prevent exudation of resin and in-` filtration of air into the resin between the surface films.

As has been mentioned above special provision has been triade for the use of surface film materials which shrink when exposed to heat. It has been found that when cellophane is employed for either or both surface films the heat applied to cure the resin causes the cellophane to shrink widthwise. The reinforcing material on the other hand does not shrink. As the reinforcing material is adhered by the resin to the surface of the cellophane, the narrowing of the cellophane causes the reinforcing maferial to bunch up into lengthwise wrinkles. In order to form a sheet of desired cross section and uniform thickness using cellophane for one or both surface films provision is made for preshrinking the cellophane and simultaneously reorienting the fibers of the reinforcing material with respect to the surface of the cellophane as shrunk.

InFigures 2 and 3 apparatus for preheating the upper and lower surface films UF and LF to shrink them is shown with mechanism for guiding the sheet material to iron out wrinkles resulting from shrinking of the surface films. The composite sheet material S described is raised from the table 13 at the discharge side of rolls 16 and 18, and bridges across to an upwardly arched bar 4 while passing between an upper heat lamp 40 and a lower heat lamp 41 which heat the upper and lower surface lrns, respectively. Because the sheet material is being pulled through the machine, shrinkage which occurs lengthwise of the direction of travel produces no appreciable etect on 'the sheet, but the transverse shrinking tends to cause lengthwise wrinkles which are ironed out by passage of the sheet in ytaut condition across the arched bar 4.

The shrinking of the upper and lower surface films does not occur instantaneously, but is a progressive action. Further wrinkles tend to form beyond the larched bar 4, therefore, resulting from the heating by lamps 40 and 4 1. The sheet is lconsequently drawn under tension across additional arched bars, including a second upwardly arched bar 42 and a `downwardly arched bar 43. The relationship of rbar 42 relative to bars 4 and 43 is Vsuch that bar 42 is offsetfrom aline joining the central por tions of bars A4 yand 43 to, iron the central vpart of `thecon-if pbsre sheet, but l'nst f the sheet width AWill not touch bar42but'willspan betwn bars 4 and 43.

Beyondthis:` downwardly 'arched br 43 `the sheet ,may

pass between additional 'heat lamps 44 above the sheet and?45i'belotvy it.' Such heating-,will'veffect fu-rEthen'shrinkf a'ge ofthe sur-faceffilms so that the composite` sheet is;

tions of the surface films to shrinkv entirely out of contact` with an engaging surface while still adequately supporting the sheet, and as the sheet is drown across the additional bars 47 and 48, the wrinkles extending lengthwise of the sheet are dissipated.

Preferably the last ironing rod 48 is located just inside the oven 5 where the composite sheet isl heated to accelerate setting of the resin. The various portions of the surface films as they reach the bar 48 will be shrunk substantially to the maximum degree to which they would Abe shrunk by the heat of the resin curing oven and consequently no material additional shrinkage of the surface films can be expected. At the same time the heating effect of lamps 40, 41, 44 and 45 will have been so small on the resin that no great reduction in fluidity of the resin will have occurred before passage across bar 48. Immediately after a sheet portion enters the oven 5, therefore, the shape of the sheet may readily be altered to any desired shape of cross section.

l The final sheet material may have any of various shapes of cross section such as corrugated, at, arched, or of other shape. The desired shape of cross section may be produced by using dies of corresponding shape which in this instance are shown as corrugated, cooperating shoes including an upper shoe 50 and a complemental lower shoe S1.V These shoes are shown best in Figures 4, 5 and 6. vAs shown in Figures 2 and 4, the first pair of such shoes is spaced a substantial distance from the entering end of the oven to enable the cure of the resin to be initiated and to guide the sheet from unwrinkled condition as it crosses bar 48 into transversely gathered shape corresponding to the corrugated conformation of the shoes at the point of entrance between the shoes of the first pair.

Arranged along the length of the curing oven 5 is a number of pairs of sheet forming shoes, all of which may be identical. A practical arrangement has been found to use shoes approximately one foot in width in the direction of travel of the sheet and spaced apart approximately thirty inches on centers, The lower shoes are stationary and serve to support the sheet as it is drawn through the ovens while at the same time exposing it to the circulating hot air of the oven. This exposure not only affords an economical transfer of heat to the sheet but also in the exotherrnic stages'of the cure allows the cireulating air of controlled temperature to carry heat away from the sheet. It may not be necessary for all the upper shoes to engage the sheet at all times. This depends upon the speed of the sheet through the oven and the rapidity of cure. The shoes do not exert any great pressure on the sheet material, for prior to appreciable setting of the resin it may be formed very easily so that it is merely necessary to preserve the cross-sectional shape of the sheet formed by the first shoes until the resin has set suliiciently so that the cross section of the sheet will be maintained accurately. The action of the shoes is more that of ironing than of compressing so that the sheet is repeatedly smoothed into the desired shape of cross section until the set resin maintains such shape by reason of its rigidity when set.

The lower shoe in each instance may be made of corrugated aluminum sheet material properly supported and covered by soft surfacing material such as'felt, having a low ,coefcient of friction. These bottom dies 5K1 maybe supported 'from the structure Yof the 'oven 5 by suitable legs 52. These lower dies willbe aligned inregistry lengthwise of the direction of movement'of the sheet material. The

upper'dies Srmay alsfbehfomied of corrugated sheet aluminum, arranged complementally to the corrugations@ in the lower shoe 51 in veach instance. The material of the upper shoes or dies may also be provided with a soft smoothing surface, such as of cloth or felt. Eventhough the upper shoes may be made principally of aluminum, it is not necessary to increase their weight to produce the proper molding effect on the sheet S, because, as mentioned previously, the resin in its initial setting stages is very soft, so that the sheet may be molded into the desired cross sectional shape corresponding to the shoes simply by the ironing action of such shoes. l

Despite the low coeicient of friction of the shoe surfaces with the sheet material being drawn between them and the slight pressure of theshoes'on the sheet material, therewill, nevertheless,.be appreciable friction between the sheet and the shoes, so that the sheet will tend`to drag the shoes with it through the-apparatus unlesslengthwise movement of the shoes.isrestrained. As mentioned previously, the lower. shoesA are supported by the legs 52, so that they cannot be moved byl travel of the sheet material across them. The upper shoes iioat on the sheet and tend to be moved edgewise with it. To restrain such movement a rod 53 is disposed at each end of the rst upperl shoe, and each such rod has one end connected to the hood ofthe oven and the other end connected to acornerof the upper shoe. Additional rods 54 are connected between adjacent edges of the upper shoes in successive die pairs.

In order to control more readily the temperature of the composite sheet as it passes through the oven, it is desirable to divide the'oyen into several sections numbered 55,56, 57 and SSin Figure l land Figure 4, arranged` in-the order in whichl the -sheet progresses. Preferably the last oven sectionds spaced. a considerable distance from the main oven in which the sections are arranged in a group.' A table section 59 bridges the gapbetween the main oven section and the final section. While the number of oven sections, the length of each, or the aggregate length of all the sections is not critical and vmay be varied according to the particular desires of the sheet manufacturer, the arrangement described is entirely practical. The reason for the oven being sectionalized is that more heat mustbe supplied in the first oven section to bring the sheet up tothe desired temperature than is necessary in subsequent oven sections to maintain the sheet at a sufficiently high temperature. In fact, setting of the resin is an exothermic reaction so that in the later stages of the curing operation the desired temperature of the sheet may be maintained with the addition of little or no heat. It has been found desirable to cure the resin in a nal step at awrelatively high temperature, and this is accomplished in the separate oven section 5S.

Heat may be supplied separately to each oven section to facilitate the control of heat and each section of the oven is shown as having heat supplied to it by two burner units in Figure l. All of these burner units designated 6 may be ofthe same type and may be manually or autor matically controlled, such as by suitable thermostatic equipment. Each burner unit includes a burner chamber 60 heated by the combustion of gas or oil, or by electric resistance units.` Since the resin is inammable, it is preferred that hot air rather than products of combustion be blown into the oven by a blower 61 driven by a motor 62. Air may be recirculated through each oven compartment through a pipe 63, such air being retreated by the heater or burner, as well as being supplemented lby air drawn into the opening 64 to replace air escaping through the slots '65 in the oven walls, through which the sheet S travels.

Spacing the pairs of shoes apart a substantial distance as described affords opportunity for direct access ofthe airV to the sheet material. Additional-exposure'of the sheet may be afforded by providing'a lifting rod 66vattached to the center of each upper `s'h'oe,"by which that shoe maybe lifted a substantialdistance above the lower shoe. As shown in Figure-.m6, the upperr end o feach rod 66 is pivotally connected to a lever arm 67, one endl of which is iixedly pivoted to a bracket 68 and the other end of which may be swung upward about its pivoted end and supported in the broken-line position shown in Figure 6 by a leg 69 pivotally mounted on it. The` mately another ten minutes, and then will be subjected' to a final heating in the neighborhood of 250 F. for a period of about five minutes. With the oven design described, therefore, the sheet will be raised to the rstf temperature'4 of the order of 180 F. during its passage through the rst oven section 55 and by about the time it reaches the second oven section 56. The heat will be vmaintained at this temperature by suitable regulation ofy the heaters as the sheet progresses through sectionsi 56 and 57, and perhaps part of the gap 59. In the first portion of section 53 the temperature will be raised toV 250 F. and held for several minutes.

Following completing of the curing cycle the formed sheet will pass into the trimming section of the apparatus shown in Figures 7 and 8. the surface films LF and UF project edgewise a considerable distance beyond the glass mat ller and are glued together. Moreover, usually a strip of clear resin which is brittle and has little strength has set beyond the glass mat.l Consequently, it is desirable to trirn the edges of the sheet back a substantial distance to leave only a glass mat reinforced resin core covered by the upper and lower surface films over the entire trimmed width or" the sheet. Such trimming may be effected by abrasive cut-off wheels 7 disposed one on each side of the sheets path of travel and driven by a motor 70 through a belt 71. Such cut-off mechanism may be supported by a bracket 72 adjustably mounted on a post 73 for vertical movement to dispose the wheels 7 in proper relationship to the sheet S. A blower duct 74 will remove dust produced by the trimming operation.

Sheets of the desired length may be cut from the continuous sheet without interrupting its travel by utilizing a traveling abrasive cut-off carriage 75, the movement of which is synchronized with the travel of the sheet." This carriage spans the sheet and is supported by legs 76 having rollers 77 riding on tracks 78 extending parallel to the direction of movement of the sheet S. The' movement of the carriage along its tracks during the sheet severing operation is synchronized with the travel of the sheet, and after the completion of a transverse cut this cutting mechanism is returned automatically to its initial position, ready to cut the sheet again when it has moved a distance equal to the next sheet unit length.

The main drive motor 8 for the sheet propelling mechanism described hereaftervdrives chain 80 to turn sprocket 81 for moving chain 82 along a path parallel to track 78, and vat the same 'speed as sheet S is moved. Carriage 7 S carries a clamp 83 which may be air-operated or elec tromagnetically operated to grip the chain when a trans-. verse cutting operation is to be initiated, and such gripping action continues until after the abrasive cut-oi wheel 84 has completed its cutting movement and h as returned to its initial position ready to make another cut'. A safety limit switch 83' may be arranged on'the clamping men ber support to engage a stop ,83" f orfdisengaging the clamp in the event thatjthe`-1normaljcontrol Axriechan'isrn fails to operate.orsuchlimifswitcli arrangement Vmay 'be utilized as anormal control if desired. T

It will be remembered thatA "Thev abrasive cutoff wheel 84 is suitably mounted on 'a traveler 8S which also carries ythe cutter drive vmotor 86 connected by a belt to the cutter and is supported by guide channels 87 of the carriage 75. These channels also carry chains 88 connected to the opposite ends of the traveler 85 for propelling it along the channels 87 and such chains are driven by an air motor or an electric motor 89 mounted on the carriage. Return of the carriage in the r direction opposite that in which it is moved by chainSZ is effected by the piston rod 9V of a fluid pressure cylinder 90, preferably air-actuated.

, Chain 82 may drive an auxiliary chain 91 turning a roll 92 on which the sheet material at the discharge side of the transverse cut-off device rests. This rol'l may have a strip of friction material such as rubber or leather 93 wound spirally about it to effect a light friction grip on the sheet material. The periphery of this roll preferably travels lsomewhat faster than the continuous portion of the sheet, so that when a sheet unit has been severed this roll will propel it away from the endless sheet gradually to deposit it on a stack of completed sheet units.

VIn the description of the apparatus thus far the vsheet material has been discussed as moving through the appara'- tus without any reference to mechanism effecting such movement. Progress of the sheet material through the apparatus is effected slowly and uniformly by cooperating endless tracks or endless tread belts including lower chains or belts 100 carrying tread bars 101 extending between them and upper chains o1' belts 102 carrying tread bars 103 extending between them. The lower chains are mounted on sprockets secured to shafts 104 and 1 05, the latter being driven by chain 8 and carrying also sprocket 81. Y

Because the entire length of the sheet material is drawn longitudinally through the apparatus by the endless tracks, it is important that the tension exerted on the sheet material be constant vand steady. Consequently, the motor 3 should have very low speed,V high torque characteristics, such as an air motor or a geared head electric motor capable of moving chain 80 slowly and without jerks while applying great power to it. The tread bars 101 of the lower track and 103 of the upper track, as shown best in Figure 9, will be formed of a shape complemental to the cross-sectional shape of the sheet, so that in the particular instance illustrated they are corrugated. Moreover, the tread bars or" the upper andrlower tracks are arranged transversely of the direction of sheet movement such that the corrugations interfit to effect intimate contact with the surfaces of the sheet. Also, the tread bars are placed close together so as to engage a large area ofthe sheet surface, and the tread bar surfaces may be made of high friction material, such as rubber, to effect a firm grip on the sheet.

With tread bars thus constructed it is not necessary that the tracks exert great clamping pressure on the sheet material. If the weight of the upper track and its supporting mechanism simply bears on the sheet material and presses it against the stationarily supported lower track, adequate traction should be afforded. To enable the weight of the upper track to be thus exerted on the sheet material, the upper track assembly may be pivotally mounted about a shaft 106 carrying the sprockets for supporting the track chains at one end, while the shaft 107 carrying the sprockets for supporting the track chains at the other end of the track is mounted on the swinging ends of arms 10, swingable about the axis of shaft 106, The swinging ends of arms 108 may be raised by links 109 connected between the swinging ends of such arms and the swinging end of a lifting lever 110, swingable about the fulcrum pivot 1711 by downward movement of the handle 112 on the other end of the lever. This' lever may be swung downwardruntil the link 109 moves across the axis of pivot 111'and engages the stop 113. In that position the upper track supporting arms k'108 will remain suspended kto hold theupper track in the broken# linepo'sitionillustratcd in Figure 7.

assauts efthe large `gripping are@ arrordedfbythf treadk bar surfaces of the upper track when it is in its' downwardly swung position engaging the upper surface o'f the sheet material asin full lines in Figure 7, iti-is not necessary to drive the upper track positively, but it may serve merely as a pressure element to hold the sheet material in firm tractive engagement with the lower track tread bars.` More positive tractive effort can be assured, however, if both the upper and lower tracks are powered, and consequently it is preferred that a chain 114 interconnect a sprocket on shaft 104 of the lower track with a sprocket on shaft 106 of the upper track. In order to drive shaft 106 in the direction opposite shaft 104 so that the lower stretch of the upper track and the upper stretch of the lower track will move in the same direction, it is necessary that the chain 114 move in a figure-eight path, as indicated in Figures 7 and 9.

In operating the apparatus the surface films, UF from roll 10 and LF from roll 11, will be drawn from their respective rolls passed about their tightcners, but their tighteners may be swung to inoperative positions, and Vthen their leading ends passed between rolls 16 and 18. These upper and lower films alone may then be drawn by hand over the rods 4 and 42, beneath rod 43, over rods 46 and 47, and beneath rod 48 into the oven. All the levers (I 677 will be raised to lift the upper shoes 50 into their yns upper positions, so that the upper and lower films may be passed between the shoes of each pair. Suitable access holes, not shown in the drawings, will be provided in the walls of the oven, through which an operator may reach tograsp the surface films .and thread them through the apparatus in this manner. y

Following the same procedure, after the surface films have been passed entirelyrthrough the oven sections 55,- S6 and 57, and across the exposed sheet supporting structure 5.9, the surface films will be threaded between the upper and lower -shoes in oven section 58. While the apparatus is being set up in this manner, the edging disks 7 may be raised out of the path of the sheet material by sliding brackets 72 upward along post 73. The surface films are then fed on between the upper and lower tracks with the arms 108 swung by lever 110 into the brokenlinc position of Figure 7. When the surface films have reached this position, the lever will be swung in a counterclockwise direction about its pivot 111, as seen in Figure 7, to` lower the upper track into engagement with the surface films. The motor 8 may then be started to being pulling the surface films mechanically through the apparatus, while the glass mat end is passed beneath roll 24, which may be raised for this purpose, and fed between the films passing between upper and lower rolls 16 and 18. Roll 16 may also be raised until an appreciable portion of the glass mat has been fed past these rolls.

Operation of the oven heaters may then be started and when the oven approaches operating temperature the surface film preheating lamps 40, 41, 44 and 45 may be turned on, appropriate upper shoes 50 lowered onto the lower shoes, roll 16 lowered to press against the lower roll 18, roll l24 lowered to its operative position, and brushes 29, 33 and 34 adjusted properly. The resin feed mechanism, including the control valve for supply pipe 2,0 and the slide valve 21 in feeder trough 2, may be set lto dispense resin, and the motor 8 energized to pull the composite sheet S through at the desired rate. Tighteners 14 and 15 will then be adjusted for the proper tension of the surface film. When the glass mat core has progressed through the final oven section 58, the edging cutters 7 may be ylowered to their operative position and the brackets 72 clamped on the posts 73 so that the resin sheet material will be cut to proper width.

Up to this `point it is not necessary that thetransverse cut-off mechanism be operated, for the cellophane or other surfacing film material .can merely bunch up at the end of the table `and `be torn off. When'the resin-sheet material 'emergesv from "between the: endless tracks, however,

the transverse cut-off mechanism may be started, andan initial reference end cut made. Thereafter the cut-off mechanism may be operated either manually as .desired or by. suitable automatic control mechanism, so that when a position on the sheet material corresponding to a desired unit end has reached the position of cut-off wheel 84, the clamp 83 will be energized to clamp chain 82, synchronizing movement of carriage 75 with lengthwise movement of the sheet. Thereupon motor 89 will be energized to transverse the traveler 85 along its guides 87, While motor 86 rotates the abrasive cut-off wheel. When the cutter has completed its movement along the carriage 75 to sever the sheet, the direction of rotation of motor 89 will be reversed to return the traveler to its initial side while the clamp 83 remains operative to move the carriage in synchronism with the sheet material. Bv suitable control mechanism, such as the limit' switch 83' and stop 83", clamp 83 then will be released and cvlinder 90 energized tov reciprocate piston rod 9 for returning carriage 75 to its initial position where it will remain until the next` unit is to be severed.

v The length of heating period and temperatures are subiect to reasonable variation. so that it is possible to alter the speed of travel of the sheet material through the forming apparatus within reasonable limits as far as the curing of the resin is concerned. Perhaps the most crit-` ical feature of the process is the time during which the glass mat soaks in the resin before the sheet is consolidated between the presser rolls 16 and 18. -In order to insure that there are no drv spots in the sheets core lacking sufficient resin distribution. and to afford ample opportunitv for the resin to displace all air originally surrounding the fibers of the glass mat. the soaking time between roll 24 and rolls 16'and 18 should be at least three-quarters of a minute. Tf the soaking time appreciahlv exceeds one and one-nuarter minutes. however, the glass fibers will be free to oat freely about in the resin and may bunch un instead of remaining in a laver of approximately uniform thickness as they are in the glass mat.

On the other hand. it may be desirable to move the sheet material through the oven at a slow sneed and relativelv low heat. or at a rapid speed and higher heat. Such movement through the oven might be varied. for example. between two feet a minute and four to six feet a minute. depending upon the length of the oven. its temperature. and the time desired to set the resin. Such wide variation in sneed cannot safely be accommodated in apparatus where the glass mat applying roll 13 and the consolidating rolls 16 and 18 are spaced apart an unvariable distance. In Figure 13 an arrangement is illustrated enabling this spacing to be altered.

In this mechanism the resin supply trough 2, the doctor blade 22. the glass mat laying roll 24, and its suoporting guide rods 25 are all mounted on a carriage 115 supported by wheels 116 running on tracks 117 extending along opposite sides of the table 13. The guide roller 12 and tightener roll 14 for the lower surface film LF are mounted far enough from the consolidated rolls 16 and 18 so that when the carriage is in its farthest position to the left, in the solid-line position shown in Figure 13, the resin will be deposited on the lower cellophane sheet a reasonabledistance ahead of roller 12. The carriage may be clamped in this position or in any other adjusted position between such solid-line position and the brokenline position shown in Figure 13 by clamps 118 which may be tightened against the bottom of rails 117.

With a movable resin supply and spreading mechanism arrangement such as shown in Figure i3, it will be evident that the resin barrier formed by the channel 3 and strip 30 shown in Figure 10 must extend to the left approximately to roll 12 irrespective of the position of the vcarriage 11S along the track and consequently will be supported from the apparatus framework independently of the doctor blade in a suitable and convenient manner.

When thesheet material is progressing through the 'apparatus relatively slowly therefore, the carriage 'willbe setin the broken-line position or at some location toward the right from the solid-line position shown inv Figure 13, so that the glass mat will not soak in the resin during its travel from roll 24 to rolls 16 and 18 too long. When the rate of travel of the sheet material through the machine is increased, however, the carriage 115 may be moved appropriately to the left so that, despite the in creased speed, the soaking time for the glass mat between roll 24 and rolls 16 and 18 may be maintained approximately the same, although the resin curing time during passage of the sheet material through the oven 5 is materially reduced.

As has been discussed above, cellophane and equivalent surfacing film materials suitable for use in the manufac ture of my sheet product shrink when heated. In the apparatus of Figures 2 and 3 the surface film material is heatedy after the surface films and interposed glass mat and resin have been assembled. While the heating at that stage may serve to preheat the resin also to some extent, heat absorbed by the resin necessarily reduces the amount of heat available for shrinking the surface film material. An alternative type of arrangement is shown in Figure 14, in which the lower surface film LF and the upper surface film UF are heated and preshrunk before they are assembled with each other, or with the resin and glass mat components.

The feeding and tensioning features of the apparatus shown in Figure 14 are the same as those shown and described in connection with Figures 2 and 3, and the parts have been designated by the samey numbers, so that it is not necessary to describe these elements further. In this mechanism, however, instead of providing the heat lamps 40, 41, 44 and 45 for heating the composite sheet S, a heat lamp 119 is mounted to direct heat on the lower surface film LF immediately after it passes the tightener roller 14, and a heat lamp 120 directs heat on the upper surface film UF shortly after it leaves the tightener 15. Shrinkage of the surface films will then begin at these locations, respectively, and because there is no additional material to absorb heat, the shrinkage action will take place much more rapidly.

' To avoid wrinkling of the lower film caused by shrinkage, the guide roller 12 is replaced by roller 121 which is of the oscillating, length-varying, slat type. Alternate slats are secured to opposite ends of the roll and cam mechanism effects relative axial movementof adjacent slats so as to continually agitate the film transversely and interrupt any tendency for the film to cling to the roll which would impede its shrinking action. At the same time such slat movement would smooth Vout the film, so that as it passes onto the table 13 it will have been shrunk completely and lie smoothly.

Similarly, the upper surface film UF passes from the zone heated by lamp 120 over an oscillating, length varying, slat roll 122, interposed between the heated zone and consolidating rolls 16 and 18. Oscillation of the slats in this roll in the same way prevents any tendency of the surface film to stick to the roll surface, and

the slat movement also exerts a smoothing effect on the l film, so that it is completely shrunk and contacts roti 16 smoothly.

I claim as my invention:

1. The method of making composite sheet material which comprises moving longitudinally a lower surface film, depositing heat settable liquid resin on such lower surface lm, during continued longitudinal movement of such lower surface film carrying the resin, laying into such liquid resin stranded reinforcing material and thereby displacing the air in such reinforcing material with resin, covering the reinforcing material and resin with an upper surface film, consolidating the intermediate resin and reinforcing material by applying pressure to the lower surface film and the upper surface film and thus forming a composite sheet, moving such vcomposite sheet longitudinally through a heated zone and thereby setting the resin, and during such movement through at least the initial portion of such heated zone engaging opposite surfaces of the composite sheet and thereby shaping into a desired form the cross-sectional configuration of the sheet.

2. The method of making composite sheet material which comprises moving longitudinally a lower -surface film, depositing heat'settable liquid resin on su'ch lower surface film, during continued longitudinal movement of such lower surface film carrying the resin, laying glass mat into such resin and thereby displacing the air in such glass mat with resin, covering the glass mat and resin with an upper surface lm, consolidating the intermediate resin and glass mat by applying pressure to the lower surface film and the upper surface lm and thus forming a composite sheet, moving such composite sheet longitudinally through a heated zone and thereby setting the resin, and during such movement through at least the initial portion of such heated zone engaging opposite surfaces of the composite sheet and thereby shaping into a desired form the cross-sectional configuration of the sheet.

3. The method of processing composite sheet material which comprises superimposing a cellophane lower surface film, an intermediate layer of liquid resin and reinforcing material and a cellophane upper surface film, shrinking the upper and lower surface films by heating them while such resin remains fluid, and while unset, and, during such film shrinking operation, smoothing the surface films and thereby eliminating therefrom wrinkles caused by such shrinking.

4. The method of processing composite sheet material which comprises laminating cellophane surface films with an intermediate layer of resin and stranded reinforcing material therebetween into a composite sheet, prior to such laminating shrinking the surface films by heating them initially, and thereafter heating the composite sheet to a tempertaure lower than the'temperature to which the surface films were heated initially and thereby setting the resin.

5. In the method of processing composite sheet material including a cellophane lower surface film, an intermediate layer of resin and reinforcing material and a cellophane upper surface lm consolidated into a composite sheet, the steps of removing wrinkles from the sheet which comprises drawing such composite sheet longitudinally, during such longitudinal drawing smoothing one side of such composite sheet concavely transversely of the direction of sheet movement, and at a subsequent location in such sheet movement smoothing the opposite side of such sheet and thereby curving such opposite side concavely transversely of the direction of sheet movement.

6. In the method of processing composite sheet material the steps of laminating two surface films with an intermediate layer of liquid binder and reinforcing material between such surface films of a width less than the width of such surface films and disposed to leave edge portions of the surface films projecting laterally beyond such intermediate reinforcing material layer, consolidating such binder and reinforcing material by applying pressure to such surface films, and gluing together the inner surfaces of such edge portions of such surface films projecting laterally beyond the intermediate reinforcing material layer and thereby retaining the liquid binder between such surface films.

7. The method of processing composite sheet material which comprises laminating two surface films with an intermediate layer of heat settable liquid resin and reinforcing material between such surface films, consolidating such resin and reinforcing material by applying pressure to such surface films and thus forming a composite sheet, moving such composite sheet longitudinally through a heated zone and thereby setting Vthe resin, during such y14 movement through vat vleast the initial portion said heated -zone engaging opposite surfaces of the composite sheet in a shape gathered transversely of its direction of movement and thereby shaping the cross-sectional configuration of the sheet into a desired form gathered transversely of its direction of movement, and between such consolidating and such engagement of the opposite sheet surfaces moving longitudinally such sheet unconfined and progressively gathering thev composite sheet transversely of its direction of movement.

8. The method of making composite sheet material which comprises laminating two surface films with an intermediate layer of heat settable liquid resin and stranded reinforcing material between such surface films, consolidating such resin and reinforcing material by applying pressure to such surface films and thus forming a composite sheet, moving such composite sheet longitudinally through a heated zone and thereby setting the resin, during such movement through at least the initial portion of said heated zone drawing such composite sheet between dies engaged with and smoothing opposite sides of such composite sheet in a shape gathered transversely of its direction of movement and thereby shaping the crosssectional configuration of the sheet into a desired form gathered transversely of its direction of movement, and between such consolidating and such die engagement moving longitudinally such sheet unconfined and progressively gathering the composite sheet transversely of its direction of movement.

9. Apparatus for processing composite sheet material, comprising supply means operable to supply superposed surface films and polymerizable liquid resin therebetween for forming composite sheet material, polymerizing means operable to set the resin between such surface films during longitudinal movement of such composite sheet material along a substantially linear path, through said poiymerizing means, complemental cooperating movable gripping members located respectively at opposite sides of such path at the discharge side of said polymerizing means for clamping therebetween a portion of such composite sheet material in which the resin is set, carrier means supporting said gripping members, and drive means moving said carrier means and said gripping members a substantial distance linearly in the direction of movement of such composite sheet material to pull it through said polymerizing means.

10. The method of making composite sheet material which comprises moving a cellophane lower surface film longitudinally, depositing on such lower film heat settable liquid resin, during continued movement of such lower film carrying liquid resin laying into the resin stranded reinforcing material, covering the reinforcing material with a cellophane upper surface film, consolidating the intermediate reinforcing material and resin by applying pressure to the lower surface film and the upper film and thus forming a composite sheet, moving such composite sheet longitudinally, and during4 such movement initially heating itsiupper and lower surfaces and thereby shrinking the surface films, during continued longitudinal movement of the composite sheet smoothing opposite .sides thereof and thereby removing wrinkles caused by shrinking of the surface films, moving the composite sheet lone gitudinally through a zone heated to a temperature lower than the temperature of initial heating and thereby setting the resin and during such movement engaging opposite surfaces of the ysheet and thereby shaping the cross-sectional configuration of the sheet during setting o f the resin.

ll. The method of making composite sheet `material which comprises moving a cellophane lower surface fili-n longitudinally, depositing on such lower film heat settable liquid resin, during continued movement of Ysuch lower filrn carrying resin laying into the resin a sheet of glass mat material and moving such sheet of glass mat material longitudinally conjointly with th lower filiii, cov;

t 15 ering the glass mat with a cellophane upper surface film, consolidating the intermediate glass mat sheet and resin by applying pressure to the lower surface film and the upper film and thus forming a composite sheet, moving such composite sheet longitudinally, and during such movement initially heating its upper and lower surfaces `and thereby shrinking the surface films, during continued longitudinal movement of the composite sheet smoothing opposite sides thereof and thereby removing wrinkles caused by shrinking of the surface films, moving the composite sheet longitudinally through a zone heated to a temperature lower than the temperature of initial heating and thereby setting the resin, and during such movement engaging opposite surfaces of the sheet and thereby shaping the cross-sectional configuration of the sheet during setting of the resin.

12. Apparatus for making composite sheet material including cellophane surface films and an intermediate layer of resin and stranded reinforcing material between such films, comprising means operable to move such surface films longitudinally with heat settable liquid resin therebetween, heating means disposed along the path of such movement and operable to heat such surface films initially and thereby shrink such films prior to setting of the resin from fiuid condition, and additional heating means disposed along such path of movement beyond said first heating means and operable to heat the resin and thereby set it after the surface films have been shrunk.

13. The apparatus defined in claim l2, and sheetsmoothing means engageable with a surface film, interposed between the heating means and operable, prior to heating of the sheet for setting the resin, to smooth from the surface film engaged thereby wrinkles caused by yshrinking of such film.

14,'A'pparatus for processing composite sheet material comprising means operable to move longitudinally a surface film, means operable to deposit liquid hinder on such film, and cooperating upper and lower elongated ridge members engageable with opposite sides of such surface film and having their lengths extending in a di- `rection substantially parallel to the direction of movement of such film limiting fiow of such binder transversely of the direction of film movement.

15. Apparatus for processing composite sheet material comprising meansoperable to move longitudinally a surface film, means operable to deposit liquid binder on such surface film, an elongated channel member having its flanges engageable by one side of such surface film and having its length extending in a direction substantially parallel to the direction of movement of such film, and a strip member disposed between the flanges of said channel member, and engaging theother side of such film and pressing it into such channel to limit flow of such [resin] binder transversely of the direction of [flow] film movement.

16. Apparatus for making composite sheet Amaterial including surface films and an intermediate layer of resin and stranded reinforcing material between such films, comprising an oven, and sheet-engaging shoes received lin said oven and spaced apart lengthwise of it and engageable respectively with portions of the surface films alternating with unconfined portions of such films for smoothingopposite sides of the composite sheet as itV is drawn between said shoes during its passage through said oven. f

17. Apparatus for making composite sheet material comprising an oven forming a heated path through which 'composite sheet material including a lower surface film, an intermediate layer of reinforcing material andresin and an upper surface film may be moved longitudinally, and cooperating endless tread belts disposed adjacent to each other at the discharge side of said oven, operable to grip therebetween a portion of such composite sheet in which the resin has set, and'being further operable to draw through said oven the composite sheet thus gripped 16 to set the resin in the portion of the sheet passing through the oven.

18. In the method of processing composite sheet material the steps of laminating two surface films with an intermediate layer of liquid resin and reinforcing material between such surface films of a width less than the width of such surface films and disposed to leave edge portions of the surface films projecting laterally beyond such intermediate reinforcing material layer, and bonding together such edge portions of such surface films projecting laterally beyond the intermediate reinforcing material layer and thereby retaining the resin between such surface films until the resin has set.

19. In the method of processing composite sheet material the steps of laminating two surface films with an intermediate layer of heat settable liquid resin and reinforcing material between such surface films of a width less than the width of such surface films and disposed to leave edge portions of the surface films projecting laterally beyond such intermediate reinforcing material layer, bonding together such edge portions of such surface films projecting laterally beyond the intermediate reinforcing material layer and thereby retaining the resin between such surface films until the resin has set, and after such bonding heating the laminate and thereby setting the resin.

20. in the method of processing composite sheet material the steps of laminating two surface films with an intermediate layer of liquid resin and reinforcing material between such surface films of a Width less than the width of such surface films and disposed to leave edge portions of the surface films projecting laterally beyond such intermediate reinforcing material layer, consolidating such resin and reinforcing material by applying pressure to such surface films, and bonding together such edge portions of such surface films projecting laterally beyond the intermediate reinforcing material layer and thereby retaining the resin between such surface films until the resin has set.

2l. The method of making composite sheet material which comprises laminating two surface films with an intermediate layer of resin and stranded reinforcing material between such `surface films, consolidating such laminate into a composite sheet, moving such composite sheet longitudinally through a heated zone and thereby setting the resin, and during such movement through at least the initial portion of said heated zone engaging opposite sides of each portion of such composite sheet intermittently, successively between dies arranged in succession in Stich heated zone, and thereby shaping into a desired form the cross-sectional configuration of the sheet.

22. The method of making composite sheet material which comprises moving longitudinally a lower surface film, depositing on such lower surface film heat settable liquid resin, during continued longitudinal movement of such lower surface film carrying the resin laying stranded [resinforcing] reinforcing material into such resin and thereby displacing the air in such reinforcing material with resin, covering the reinforcing material and resin with an upper surface film, consolidating the intermediate resin and reinforcing material by applying pressure to the lower surface film and the upper surface film and thus forming a composite sheet, moving such composite sheet longitudinally through a heated zone and thereby setting the resin, and during such movement through at least the initial portion of such heated zone deforming the composite sheet from planar shape into a shape gathered transversely of its direction of movement by engaging opposite surfaces of the composite sheet and thereby shaping into a desired nonplanar form the cross-sectional configuration of the sheet.

23. The method of processing composite sheet material which comprises superimposing a cellophane lower Surface film, an intermediate layerof liquid resin and reinforcing material and a cellophane upper surface film,

surface lm's with 'the resin therebetween to a tempera` ture lowerrthan the temperatureto which the surface {llns were 'heated initially "and therebylsetting Y'the resin 4.25. Apparatus'forprces'sing composite sheet material "'mp'rising a iilrn 'supporting table, viiieans operable to finve `a film longitudinally along Ysuch table, two elonlI-'g'a'ted ridge 'elerriei'lts` having vtheir lengths extending parallelv to' the direction 'ofnioveincnt lof the hlm; spacedfapart "a substantial distance "t siv'ers'ely "of such direction 'of til'm movementnalperame tpjl'iftportions of themm fpverlying said ridge lements above the film portion ou the tablebetween able Vto deposit 'liquid er onfsuchflin between "said diri re elements, andmeans oper-v 'ridge elements, vs'a. fridgel mentsbeing operable to deter s 2'6.'Af method 'f cotinuouslyforming a thermosetting 'p'lastic product of predetermined cross section, compris- .ing depositinga liquidfpool'of `the'rrn'osetting resin on a moving, resin-impervious flexible flm depositing reinforcing material onto the moving resin, incorporating 'fthe reinforcing material Tinto the body of liquid resin, covering the 'reinforced resin with another-resin-impervious flexible film to :form an/'eticasedreinforced resin, partially curing the encased 'reinforced'resin heating, llo'cating the partially cured vencased reinforcedresin'between molding members, and heating the resin while so located to advance the curing thereof.

27. A method of continuously forminga fibrous reinforced thermosetting plastic product, comprising moving a continuous flexible filmalongj a predetermined path, deflecting opposed marginal edgesof said film upwardly to give the film a trough-like conguration, depositing a liquid thermosetting plastic upon the trough-like moving film, incorporating fibrous reinforcing material into Vthe plastic, and directing heat at the fibrous reinforced plastic to advance the curing thereof.

28. A method of forming a fiber reinforced resin panel, comprising depositing a layer of flowable liquid thermosetting resin on a flexible resin-impervious sheet, progressively moving a matted layer of bers downwardly into the layer of resin to submerge Vsaid fibers in liquid resin, positioning a flexible resin-impervious cover sheet on the layer of fiber reinforced resin to form a laminate, squeezing excess air from between tite resinous-impervious sheets, locating the laminate between molding members to form said laminate to a predetermined configuration and then heating the laminate to cure the resin layer.

29. A method of forming a fiber reinforced resin panel as defined in claim 28, wherein prior to locating the laminate between the molding members the laminatey is heated whereby the cure of the resin is initialed, and the resin is very soft when the sheet is disposed between the molding members.

30. A method of forming a fiber reinforced resin panel, comprising depositing a layer of fiowable liquid thermosetting resin upon a flexible resin-impervious sheet, progressively moving a glass fiber mat into the layer of resin along the length thereof, positioning a flexible resinimpervious cover sheet on the layer of fiber reinforced pasttlie'm 'transversely of y'the' 'as-,sin

resin tp form .a laminare, locating tire temmen u'pbn a mold having cbnvexly curved upper surface portions, smoothing the laminate aftersaid laminate is in Contact with said mold to remove wrinkles from athe laminate and conform 'the laminate to the mold surface, and heating the laminate lwhile in contact with said mold to cure the resin.

31. A method of continuously forming a thermosetting plastic product of predetermined cross section, comprising depositing liquid thermosetting resx'n onto a flexible surface being moved, depositing reinforcing fibers onto 'th'e moving liquid resin, covering the reinforced rest'n formed with another flexible surface to form an encased liquid resin having reinforcing fibers embedded therein, partially curing the encased reinforced resin by heating, thereafter moving the 'encased'partiall'y cured resin through a yforming means, 'and heating-such encased partially cur'ed 'resv'n 'while being moved through such forming ma'rtsto advance the curing ofthe reinforced resin. n

32. A method of continuously forming a thermosetting plastic product of predetermined cross section, Aisom- Vprising depositingliquid thermosetting resin von a flexible film being trtlived; Y'controlling the quantity and distribu-` r` tion voffresi):,de'lfubst'ted on the moving flexible film, moving vreinforcingV bers downward into themoving ,liquid resin,co' vering eA reinforced renin with anotherffle'xible cased reinforced resin, partially-curing orced liquid resin by heating, thereafter' moving fthe fencased partially cured reinforced Y resin throughV aformng' means of predetermined cross section,

and heating such .encased partiallycuredj resin whilebeing "moved-through such-forming means to advance the curing:

of the.`reinforcedresin. t

33. 'A method -of continuously forminga reinforced thermo'settingplasticproduct of predetermined crosssection, Zcomprising continuously moving a flexiblel film,

forming d channel in uthe moving .flexible film, .depositing liquid thermosettingiresin in the-channel, depositing reinforcing fibers ontothe-liquid therm'osettingy resin, thereaftendepositing a'second. flexible film on the liquid th'ei'.- mosetting resin-to encase completely the liquid` thermosettingresin and reinforcing fibers, and advancing the resin and reinforcing ,bers through aforming means of predetermined cross section duringcuring of such resin.

34. An apparatus for continuously producing a plastic productof predetermined cross section, comprising means for providing a moving flexible film, a trough for depositing liquid resx'n on the film, means for Vdepositing fibrous reinforcing material onto t `e yliquia' resin and lowering Vthe reinforcing material v,into the vliquid resin, means for placinga second flexible film onthe liquid resin and reinforcing material, heating means for partially curing the liquid resin, forming means of predetermined cross section spaced from said heating means, means to pull the flexible lms with the partially cured resin therebetween through the forming means, and additional heating means disposed adjacent to the forming meansto cure substantially completely the partially cured resin while it is being moved through said forming means.

35. Apparatus of the character defined in claim 34, in which there is provided means adjacent the trough for accurately controlling the quantity and distribution of liquid resin deposited on the continuous film.

36. An apparatus for continuously producing a plastic product of predetermined cross section', comprising means for providing a moving flexible film, guide rails beneath each side edge portion of the flexible hlm, a trough for depositing liquid resin on the flexible film, means for depositing glass ,fibers onto the liquid resin and moving the glass bers downward into the liquid resin, means for placing a second' flexible hlm on the liquid resin containing the fibers imbedded therein, means for pressing out entrained air from between the first and second flexible films, heating means for partially curing the liquid resin, forming means of predetermined cross section spaced from said "heating means, means to pull the flexible films with the partially cured resin therebetween through the forming means, and additional h eating means disposed Yadjacent to the forming means to cure substantially completely the partially' cured resin while it is being moved through said forming means.

37. A method of continuously shaping a continuous moving laminate including a layer of liquid resin containing reinforcing fibers and sandwiched between a pair of resin-impervious fiexible sheets, comprising curing the moving layer of resin to a very soft condition in its` initial setting stages, moving the resin in such com dition through a forming means of predetermined cross section, and advancing the cure of the resin while the 'laminate' is being moved through the forming means.

38'. A method of continuously shaping a vvcontinuous'l vmoving laminate includingQa layer of liquid Ythermolsetting resin containing reinforcingl fibers and sandwiched between a pair of resin-impervious flexible sheets, comprising heating the moving laminate to cure the resin to a very soft4 condition in itsinitial setting stages, moving the laminate through a forming means off 'predetermined cross section with the resin in such condition, and heating the moving laminate while passing through the forming means to advance the' cure of the resin.

39. A method of continuously corrugating a continuousmoving laminate including a layer of liquid thermosetting resin containing reinforcing fibers and sandwiched between a pair 'of resin-impervious flexible sheets, comprising heating such moving laminate to cure the `resin partially, continuously ydirecting the under Vsurface ofthe moving laminate overa formingV surface having corrugations extending substantially parallel to 'the 'path of travel of the laminate, applying pressure vto the upper surface ofthe laminate to conform the laminate to 'the configuration of the forming surface, and heating the laminate while in contact with the forming surface to advance the resin cure.

` 40. Apparatus for continuously producing shaped plastic panels of predetermined cross section from a continuous laminate including a layer of liquid thermosetting resin containing fiber Vreinforcement and sandwiched between a pair of.resinimpervious fiexible sheets, comprising' means for moving such laminate along a predetermined path, means to apply heat to the laminate while moving along such path to cure the resin partially, form- References Cited in the le of this patent or the origlnal patent UNITED STATES 1 ATE1-1TS 1,270,250." Schenkelberger June 18, 1918 1,449,912 Respess ,Mar. 27, 1923:- 1,885,280 Moore v Nov. .1, 1932 2,193,861 'Crowley Mar. 19, 1940 2,343,600 Weimann Mar. 7, 1944 2,407,548 Goldman Sept. 10, 1946 2,456,923 Cogovan et al. Dec. 21, 1948 2,476,282 Castellan July 19, 1949 2,476,582 Browne et a1. July 19', 1949 A2,523,022 Horstman Sept. 19, 1950 2,526,945 1950 2,561,781 Bruce July 24, 1951 2,562,641 `Saunders July 31, 1951 2,571,717 Howald et al. Oct. 16, 1951 2,625,498 Koch Ian. 1,3, 1953 2,626,883 Boese Ian. 27, 1953 2,631,955 Muscat Mar. 17, 1953 2,637,673 Barnard May 5, 1953 2,662,044 Morrison et a1. Deo. 8, 1953 2,671,306 Slayter Mar. 9, 195,4 2,704,734 Draper et al.` Mar. 22, 1955 2,737,701 Hubbard. et al. Mar. 13, 1956 FOREIGN PATENTS GreapBritain Apr. 21, 1949 

